1. Field of the Invention
The present invention relates generally to the manufacture of abrasion-resistant safety garments, and more particularly to a conformal-beaded matrix which may be incorporated within garments to protect the wearer from abrasion.
2. Background of the Description
Various forms of safety garments have been created for use in sports such as motorcycling, bicycling, skating, skateboarding. Many of these garments incorporate impact absorbing areas and abrasion resistant materials which improve wearer safety. The protection offered by these safety garments fall into two main categories: impact protection and abrasion protection. Padded areas, often within resilient cups that may be constructed of materials such as Temperfoam(trademark), are often sewn into garments over impact-sensitive areas, such as over the knees, elbows, shoulders, ankles, and even over the spine. These impact absorbing sections are often referred to as xe2x80x9cbody armorxe2x80x9d. Densely woven materials, generally provided in layers, are used within these safety garments for preventing abrasion over the remaining fleshy areas of the user. Traditionally one of the best materials for these safety garments has been thick leather (i.e. over 1.5 mm), as it provides abrasion resistance many times greater than traditional cloth materials. Newer materials such as ballistic nylon, Cordura(trademark), Gortex(trademark), Kevlar(trademark), along with armor sections, are being incorporated within otherwise traditionally constructed cloth garments in order to increase their abrasion resistance. These garments rely on the use of layers of dense durable abrasion resistant cloth materials to protect the wearer.
Often minor abrasions are referred to as xe2x80x9croad rashxe2x80x9d wherein a slowly moving body contacts a roadway surface at a speed of under 15-20 mph. However in sports such as motorcycle riding, a fall at even moderate speed on a roadway surface can result in severe abrasions; whereby not only the skin is abraded away, but significant amounts of flesh, muscle, and bone can be similarly removed. Even moderate abrasion wounds are painful and slow healing. Severe abrasion wounds can result in a significant blood loss, an infection hazard, a likelihood of permanent disfigurement, and even death.
Everyday clothing provides insignificant levels of abrasion resistance, such as to a motorcycle rider falling on a roadway. In Australia in 1982, the Royal Brisbane Hospital Burn Unit completed a 13xc2xd year study of motorcycle burn injuries wherein 29% of the burn unit victims were road abrasion burns with 46% experiencing the burns to both upper and lower extremities. Of these the median hospital stay was 8 days, but ranged up to 186 days. It was concluded that proper safety clothing would have prevented all of these road abrasion burns. Similar studies have been conducted in England, Germany and other countries with similar results.
Insurance industry and government committees have been looking closely into regulations directed at safety garments. At this time Germany is considering compulsory clothing standards which require motorcycle riders to wear certified safety garments, while the British Standards Institute of the British government is drafting standards for protective clothing for motorcycle riders.
As can be seen, therefore, abrasion-resistant protective clothing should be worn when one is involved an any high speed activity where one is otherwise unprotected from abrasion as a result of a fall. However, the use of protective clothing is often ignored, even though equipment currently exists which can largely protect riders from impact and abrasion injuries. Part of the lack of acceptance of current safety garments may lie in the numerous drawbacks that are inherent in the designs which limit their proper habitual use.
There are generally two principle forms of safety garments available for sports such as motorcycle riding; the first category is leathers, while the second is cloth type garments. Thick leather provides a good measure of protection and is favored by the majority of competitive riders. Its thickness and durability often requires that only a single layer is required to prevent abrasion. However the leather does not stretch nor does it allow air-flow to reach the wearer. Protection in the, many current cloth-type safety garments is provided by means similar to those used within ballistic protection gear, such as so called xe2x80x9cbullet proof vestsxe2x80x9d; wherein a tightly closed material structure is created through which no objects can incur. Layers of densely woven Kevlar(trademark) and carbon fibers have replaced steel chain-mail type construction in these protection suits. Within an abrasion resistant garment, numerous layers of material are utilized to provide redundancy as a layer wears through during a fall, and to provide thermal insulation. To further enhance protection against abrasion, more ballistic armor techniques have been considered, such as covering the exterior of the garment with closely spaced platelets. Within ballistic protection suits the platelets are intended to prevent ballistic incursion, but in this case have been considered to prevent roadway incursion. However, it will be appreciated that such approaches lead to the creation of a heavy garment that is substantially covered with anti-ballistic material. Opening up platelet spacing then leads not only to a garment that tears on impact, but one in which the friction forces rotate platelets, platelet halves, or platelet fragments, against the skin of the wearer inflicting additional injury. In general, abrasion resistant clothing follows the teachings of ballistic protection to provide abrasion protection.
Unfortunately, both the leather and cloth designs, when promulgated as abrasion safety garments, restrict air-flow and consequently when worn in warm to hot weather are at best uncomfortable, and may in fact be unwearable, due to the high risk of hyperthermia. Thick garments such as these allow insignificant amounts of air to flow and thereby pose a dangerous hyperthermia risk as body temperatures can soar. It is not surprising that a large percentage of safety-conscious riders don""t ride when it gets warm out, . . . while others ride dangerous underprotected with street clothing. Clothing manufacturers have worked to provide various forms of venting for conventional safety garments, however, venting is unable to compensate for the bulk of layers of tightly woven material surrounding the wearer, and vents are of only minor aid when the wearer is stationary. To fully appreciate the situation, it should also be remembered that in the case of a motorcycle rider, the rider is seated above an engine operating at high temperature, the heat from which rises to envelop the rider.
Accordingly there is a need for abrasion resistant safety garments that can be constructed to minimally restrict ventilation of the wearer. The abrasion resistant conformal beaded-matrix in accordance with the present invention satisfies that need, as well as others, and overcomes deficiencies in previously known techniques.
The present invention is an abrasion resistant garment and method of garment construction that employs round beads held within a two-dimensional open matrix of abrasion-resistant cords. Abrasion resistant beads with low levels of abrasive friction are attached within a crossing matrix of abrasion resistant cords. Constructed within a garment, the bead matrix allows a high degree of ventilation as it covers only a small percentage of skin surface; yet it can provide high levels of abrasion resistance to enhance the safety of sports such as motorcycle riding.
Within the current invention it has been recognized that abrasion resistance is not an analogous problem to that of ballistic protection. Presently, abrasion resistant garments solve the abrasion problem at a micro-level wherein incursion through the fabric is considered throughout the span of fabric. Therefore, the fabric must be of a substantially uniform nature wherein no portions of the skin are to be subject to surfacial contact, being held apart from the road surface by a series of layers. It should be noted that these garments modeled on ballistic principles do provide a level of ballistic (puncture) resistance, however, puncture-type injuries are not a primary source of injury during the majority of incidents. The current invention has eschewed the approach taken in ballistic protection garments and adopted a macro-level approach to the reduction of abrasion, whereby the pliable skin is treated as a integral surface as opposed to a collection of singularities. Within the invention, the skin of the wearer is held off of the pavement surface by abrasion-resistive beads periodically placed within an open matrix. Air flowing between the skin and surface insulate the skin of the wearer from the abrasive surface. The abrasion between the garment and the road surface takes place on the exterior of protruding beads while a large percentage of the skin is not covered by bead, yet is still protected by being retained within the matrix of supporting cords which span between the beads to thereby support the fleshy areas.
The following is an example that may aid visualization of this force distribution concept. Many people have watched in amazement as eastern mystics lie down on a bed of sharp nails and then rise again unscathed. These nails are sharp, and quite obviously any one of these nails can penetrate the skin. However when the force of the body is distributed across a number of these projections the force at each projection is insufficient to cause incursion of the skin surface by any one nail. The person laying down does not need a bullet proof vest (micro-level concept) to prevent a nail from injuring them, they only need to distribute the forces being applied (macro-level concept). The method according to the invention isolates abrasive forces at a series of bead contact points between the wearer and the roadway surface under sliding contact. In similar manner to the xe2x80x9cbed of nailsxe2x80x9d, the force across the beaded matrix is thereby distributed. Unlike the bed of nails, the wearer need not be careful of the rate at which the pressure is applied over the matrix, as the shape of each bead supports increasing loads the further it is depressed against the skin.
Each bead within the cord matrix is formed of a material which provides a low sliding resistance when contacting the road surface. These beads extending from the skin""s surface bear the majority of the pressure from the rider. The conformal matrix is preferably constructed with integral elastic within the cords of the matrix which retain the beads near the skin surface, and which are capable of only limited stretch under frictional load. An important safety factor within the material occurs under abrasive friction, whereupon the beads rotate to tighten the attached matrix of cords to suspend the skin above the roadway surface between separated bead xe2x80x9cpillarsxe2x80x9d. The beads are configured with limited attachment points, preferably four to six, which retain them within the cord matrix while facilitating bead rotation. The beads have a substantially round surface in either one or two dimensions, and may rotate under urging such that side areas of the bead are exposed to the abrading surface. Preferably the beads are configured as either spheres, or oval cylinders. The beads are therefore provided with limited rotation, while they simultaneously take up the slack in the cord matrix to properly retain and suspend the fleshy portions of the wearers skin riding above the beads.
In constructing a safety garment, it is preferably that the conformal beaded matrix be interrupted over the boney areas such as knees, shoulders, elbows, ankles, and spine to incorporate shock absorbing structures, such as body armor sections of conventional construction. It will be appreciated that although the beaded matrix provides a high degree of abrasion protection while providing for air-flow, it provides very limited impact resistance. Although the beaded matrix could be created as a single layer garment, it is preferable that the beaded matrix be sandwiched between layers of thin open-weave breathable cloth to improve appearance and for the incorporation of reflective material. The beaded matrix can be incorporated in garments constructed for any season of use depending on the number and composition of the layers employed.
This method of providing abrasion safety departs from that of prior garments in a number of respects. The open nature of the material allows for very high levels of ventilation to be provided in a garment without compromising safety from road abrasion. Garments produced therefrom can be worn comfortably on even the hottest of days. The present invention should have lower weight, increased airflow, and added safety when compared with conventional safety garments modeled after ballistic suits, or ballistic suits which consider the use of exterior platelets. Expanding the distance between the tiny plates attached over a conventional ballistic style safety garment to lighten the suit and provide for airflow does not yield similar results as the present invention and may pose a safety risk. In an abrasive sliding situation the edges of these plates catch the ground and rotate, this increases garment tearing while the opposing exposed edges of the plate are driven into the wearer""s flesh. Such a plate can easily be driven into a near-surface bone, such as a shin-bone, to cause a fracture. Providing space between surface platelets, therefore, allows the edges to become vulnerable to catching the ground. As an edge catches, the cloth surrounding it is in contact with the surface of the ground, caught between the hard edge of the small plate and the hard road surface, such that the two in concert can grind through even abrasive resistant cloth. In addition the conventional construction of platelets have employed metals or ceramics, which although durable, create high levels of interface friction between the garment and the roadway surface. The high degree of friction causes high rotational torque on the sliding rider""s body, thus increasing the extent of tumbling related injuries.
Within the beaded matrix of the invention, each bead retains a round portion against the skin and a similar portion which is in contact with the ground during a slide, there is no transition region, such as the edge of a plate, during rotation of the bead element. It will be appreciated that the beads retained in the matrix may be of differing sizes in accord with the level of abrasive forces which may exist over that area. For example, the skin surfaces of the inner thighs, between the legs, are subject to far less abrasive risk than the anterior portions near the hips. In some areas, such as the crotch or under the arms, the inclusion of beads within the matrix may be forgone altogether. The rounded outer surface areas of each bead slides on the pavement surface easily without catching, and the inner surface areas of each bead make smooth contact with the wearers skin, applying smooth pressure gradients around the contact points of the beads, without projecting edge regions into the skin or bone of the wearer. The soft abrasion resistant beads, therefore, can partially rotate while maintaining a smoothly contoured exterior which is not prone to catching the surface of the road, and a smoothly contoured interior which will not lacerate the rider. In addition, the rotation of a section of beads enhances the safety of the garment as it causes the underlying matrix to tighten up to hold the skin away from the road surface more effectively. The use of a conventional cloth material to retain the beads is not preferred as the material then divides the bead into a lower and upper half and creates a transition region about the annular periphery where the cloth exits the bead. A conventional cloth material substantially inhibits bead rotation that provides the increased skin retention forces, while the continuous span of cloth itself then becomes subject to tearing. In contrast, the cord material of the matrix forms a very open structure, which allows each cord within the matrix to be configured with even large diameter cords, for instance {fraction (1/16)} to xe2x85x9 inch, without significantly reducing airflow and flexibility, or unduly increasing cost. The large diameter of the cord material can be produced with a very high resistance to abrasive wear-through. Also the beads, being of a soft material, do not act in concert with the road surface to abrade the surrounding matrix. Moving against a surface of skin under compressive oscillating friction, the beads should also induce lower levels of friction heating against the skin surface when compared to cloth.
An object of the invention is to provide abrasion-resistant garments that can be constructed to provide improved ventilation.
Another object of the invention is to provide a material for the abrasion-resistant garment in which only a small surface of the wearers skin need be covered with the closed portions of material comprising the garment.
Another object of the invention is to create a method of providing abrasion resistance within a garment that may additionally employ protective armor sections over boney area such as the knees, elbows, shoulders, ankles, and spine.
Another object of the invention is to provide abrasion-resistant garments that can be worn with or without exterior layers for retaining warmth.
Another object of the invention is to provide abrasion-resistant garments that do not impose high rotational torque forces on fallen riders which can lead to additional injury.
Another object of the invention is to provide abrasion-resistant garments wherein the frictional forces on the exterior beads during a slide tighten up the garment to restrict contact of integument with the pavement surface.
Another object of the invention is to provide a method of obtaining abrasion resistance that does not rely on the use of a continuous span of material coverage.
Another object of the invention is to allow for the creation of abrasion-resistant garments which may be easily manufactured at low cost.
Further objects and advantages of the invention will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the invention without placing limitations thereon.